The number tells you how the temperature outside really feels, and you can even calculate it yourself using a really long equation.
Temps in the 90s are expected in parts of the Bay Area, with some areas nearing triple digits on Wednesday as a heat spell continues across the region.
A heat advisory has also been issued due to the high temps.
While it is routine for many of us to review forecasted temps, you'll likely see meteorologists discuss the heat index as part of their weather coverage.
What exactly is the heat index?
The number tells you how the temperature outside really feels, and you can even calculate it yourself using a really long equation.
Watch an explanation in the video above.
Meteorologist Kari Hall has details on one more day of triple-digit heat inland and sneaker waves on the coast, with a cool-down in the weekend Microclimate Forecast.
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